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Information × Registration Number 0215U001369, 0113U001078 , R & D reports Title The creation and study of new material on the base of nanocomposite of zirconium dioxide and HTSC-composites for polyfunctional purposes popup.stage_title Head Vovk Ruslan V., Доктор фізико-математичних наук Registration Date 16-02-2015 Organization Kharkov National University named after V.N. Karazin popup.description2 Objects of research: Y1-уPrуBa2Cu3O7-?, Y1Ba2Cu3O7-?, ZrO2-WC composite. Purpose of research: Establishment of the influence of structure and method for production on some physical properties of materials. The method of research: the study of electrical resistivity, in particular, under high pressure; thermal conductivity, thermal linear expansion. The temperature dependence of the resistivity of YBa2Cu3O7- and Y1-уPrуBa2Cu3O7-? single crystals at different orientations, temperatures, compositions, pressures and times determined by the scattering of electrons by phonons and defects with the transition to a "semiconductor" type of resistivity at growth y or , as well as the fluctuation conductivity near Tc. For Y1-уPrуBa2Cu3O7-? all mechanisms of conductivity and carrier scattering is anisotropic, which determines the anisotropy of the total resistance. The increase in pressure causes a redistribution of labile oxygen, which can be considered reversible, but the relaxation times of individual processes of conduction and scattering of charge carriers are significantly different from each other. The long-term aging (17 years) of the optimally doped YBa2Cu3O7- single crystal in air at room temperature leads to the disintegration of the sample into phases with different temperatures of the superconducting transition. The structure of the composite ZrO2-WC is optimal when the content of WC is about 20 wt.%. This provides the best combination of hardness, strength and crack resistance. The highest density of the composite grains with a minimum size is provided by hot pressing at 1350 °C, at pressure of 30 MPa and at holding time 2 minutes of passing of direct electrical current. Thus there is a penetration of carbon atoms in the crystal lattice of the zirconium dioxide, which increases the strength at the interfaces. Elevated levels of tungsten monocarbide content increases the W2C content, which increases the hardness of the composite, thus reducing the strength and fracture toughness. It is offered the recommendations on use of the results when creating the latest models of electronic and telecommunications equipment. Product Description popup.authors Вовк Р. Геворкян Е. Гриб О. Давиденко А. Самойлов О. Хаджай Г. popup.nrat_date 2020-04-02 Close